The present invention relates to electronic or computationally based modeling applications that model physical entities, such as structures, mechanisms, or devices. Some example modeling applications that can model physical entities include Modelica (an international, independent modeling language), 20-Sim (provided by Controllab Products B.V. of the Netherlands), and Saber® VHDL-AMS (provided by Synopsys, Inc. of Mountain View, Calif.) are physical modeling languages and allow for structural elements. Some additional representative physical modeling languages include SimMechanics™, SimPowerSystems™, and SimDriveline™, all offered by The MathWorks, Inc., of Natick, Mass. SimMechanics™ simulates the motion of mechanical devices and generates mechanical performance measurements associated with this motion. SimPowerSystems™ provides tools for modeling and simulating basic electrical circuits and detailed electrical power systems. SimDriveline™ provides tools for modeling and simulating the mechanics of driveline (drivetrain) systems.
All of the above mentioned applications, in addition to others not specifically mentioned, are physical modeling applications. However, none of the known modeling or simulation applications allows modeling of a physical structure that varies structurally and maintains functionally defined physical behaviors. Rather, the modeling and simulation applications require a static or declarative structure in much the same way that the C programming language requires the programmer to declare the fields of a structure.